A Calorie is NOT a Calorie

In 1890, a chemist named Wilbur Atwater discovered that the amount of energy in food could be determined by burning it to ash (in a device called the calorimeter) and measuring the heat produced. According to Atwater, one calorie equaled “the amount of heat required to raise the temperature of one gram of water by one degree.” And surprisingly this is still the measurement used today to determine the calorie content in different foods.

But the question is, does it make sense to think that our body operates just like Wilburs oven?

We know the human body is complex; with its intricate networks consistently adjusting and readjusting based on a variety of internal and external factors.  So, does it seem reasonable to think that nothing else determines if we store or lose?

That “a calorie, is a calorie, is a calorie” as they say:


Sadly, calorie counting is still the customary advice from fitness and nutrition ‘experts,’ despite extensive scientific support suggesting otherwise. For instance, here’s a recent quote from the president-elect of the International Association for the Study of Obesity:

“Thinking that a specific diet should eliminate people’s weight problems is totally unrealistic, there is no getting around the laws of thermodynamics.”

In other words, losing weight is a battle of Calories-In vs. Calories-Out (CICO), and has nothing to do with what type of food we consume. The reason we have an obesity problem is because we eat too much and don’t exercise enough.


But if this were true, one would expect 3 unique diets with the same total calories to produce identical results in weight-loss if this were true. Right?

Fortunately, researchers in 1957 did just that, by putting participants on 1 of 3 1000-calorie diets and varying the percentages of each macronutrient – 90% fat, 90% carbs, or 90% protein.

The 90% protein and 90% fat groups lost between 0.6 and 0.9 lbs per day, while the 90% carb group actually gained!

Interestingly, any other scientific theory would’ve been discredited as soon as there was any evidence that invalidated it (like this). But somehow the CICO hypothesis lives on.

Even more interesting, is that this is just one example of many. With the chart below showing the change in % of food ‘type’ for teenagers (11-18yrs) in the U.S. from 1965 to 1991 being another good one.


Total calories, fat and protein have all decreased, yet obesity has steadily increased over this same time period?

Simply put, this is because it’s not the number of calories in a meal, it’s the composition of those calories.

Stay Lean!

Coach Mike